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• The final design solution is a balloon similar in
shape in size to balloons currently used, but
features channels for blood to flow through.
• The profile of the balloon involves a tapered end
to direct blood flow into the channels and will be
made of a non-compliant PET material to hold
the shape and prevent closing of the channels.
• The flow simulation conducted showed there is
minimal flow reduction with this design, around
30% reduction in flow.
• Due to the Venturi effect present in this flow
simulation, an increase in velocity and decrease
in pressure will occur, ensuring balloon form will
remain constant.
DESIGN
SUMMARY
DELIVERABLE
REFERENCES
• A detailed SolidWorks drawing that could be
used as patent application art
• A simple, 5 slide PowerPoint presentation
describing and illustrating the clinical and
engineering problems and our solution
OBJECTIVEBACKGROUND
• Aortic Aneurysms: abnormal widening of the aorta
due to weakening of aortic wall.
• In 2009, over 10,000 reported deaths were caused
by aortic aneurysms in the US [1].
• Occur in both thoracic and abdominal aorta
• Most common cause is atherosclerosis, or
hardening of the artery so the vessel is less elastic
[2].
• Leads to:
o Aortic dissection: blood leaks out of
inner aortic wall layer
o Rupture: outer layer tears open
• Current treatment: endovascular stent graft repair
and balloon angioplasty
o Stent graft materials: nitinol and
Gore-Tex
• Problems with current procedure:
o Balloon completely blocks blood flow,
which leads to a large spike in blood
pressure [3].
o Improper positioning could result –
average of 1.7 stents/patient
o Higher restenosis rates [4].
Current expansion techniques are problematic, as
they cause occlusion, or a blockage of blood flow at
the expansion site, interrupting blood supply to the
body. There is a need for a noninvasive mechanism
that will successfully expand the implanted stent
graft to the arterial wall with decreased occlusion of
blood flow during the standard insertion procedure.
PROBLEM
CONSTRAINTS
AND CRITERIA
CONSTRAINT CRITERIA
Non-occluding
Less than 50% flow reduction
distal to device with at least 2.5
L/min cardiac output flow
Performs necessary
function
Successfully seals the implanted
stent graft to the inner wall of
the aorta [5]
Biocompatible
Made of materials known to be
biocompatible and previously
utilized in the medical field
Compatible with
current procedure
Able to be inserted/removed via
catheter into 6 mm femoral
artery insertion [6]
User feedback of
attachment progress
Surgeon can detect pressure of
expansion device from arterial
wall at about 10 atm [7]
DECISION MATRIX
Development of a Non-Occluding Stent Graft Expansion Device
Group Ten: Christopher Davidson, Samantha Nelson, Jaideep Sahni, Halle Swann
Clients: Jason MacTaggart, M.D. and Alexey Kamenskiy, Ph.D. - Faculty Managers: Nicole Iverson, Ph.D. and Angela Pannier, Ph.D.
• To design a device that seals an implanted stent
graft onto an adjacent wall of the aortic arch
with less than 50% flow reduction distal to the
device at any time during aortic aneurysm
treatment.
Figure 3: Dimetric view of catheter assembly with flow velocity
projections.
Figure 2: SolidWorks drawing of final balloon solution.
Figure 4: Side view of catheter assembly with flow velocity
projections.
Figure 1: Schematic illustration of aortic aneurysm.
Table 1: Constraints and Criteria
Table 2: Potential Solution Decision Matrix (on a 310 scale)
[1] Kochanek KD, Xu JQ, Murphy SL, Miniño AM, Kung HC. Deaths: final data for 2009.
Natl Vital Stat Rep 2011;60(3).
[2] Aortic Aneurysm Fact Sheet. Centers for Disease Control and Prevention. July 22,
2014.
[3] Masson J, Kovac J, Schuler G et al. Transcatheter aortic valve implantation: Review of
the nature, management, and avoidance of procedural complications. J Am Coll Cardiol
Int 2009;2(9):811-820.
[4] Schuster I, Dorfmeister M, Scheuter-Mlaker S, Gottardi R, Hoebartner M, Roedler S, et
al. Endovascular and Conventional Treatment of Thoracic Aortic Aneurysms: A
Comparison of Costs. Ann Thorac Surg 2009;87:1801-1805.e6.
[5] Hamed Azarnoush. 2012. Modeling and Control of Angioplasty Balloon Deployment
Based on Intravascular Optical Coherence Tomography. Ph.D. Dissertation. McGill
University, Montreal, Que., Canada, Canada. Advisor(s) Benoit Boulet. AAINR79136.
[6] Bhogal, Ricky Harminder, and Richard Downing. "The Evolution of Aortic Aneurysm
Repair: Past Lessons and Future Directions." (2011): 21-54.
[7] Babineau, Timothy J., et al. "The cost of operative training for surgical residents."
Archives of surgery 139.4 (2004): 366-370.